Regioselective synthesis of oxazole derivatives via palladium-catalyzed and copper-mediated cascade oxidative cyclization

A novel Pd-catalyzed/Cu-mediated oxidative cyclization has been developed for the synthesis of trisubstituted oxazoles, which is thought to proceed through cascade formation of C-N and C-O bonds. In this protocol, four hydrogen atoms were removed and water was used as the oxygen atom source.